This article appears to be discussing a meeting discussing the initial response, and criticizing the initial lack of information. It appears to be a 'hearing'-type meeting about how to fix things in the future, not about an ongoing problem.
For example: The official said other member countries also criticized Japan's initial emergency response. They said they could not fully explain to their nationals what was happening as Japan failed to release detailed information immediately after the accident.
The quote you lifted says: the group was unable to obtain necessary information, again suggesting this is discussing a problem they ran into in the past.
If they were having trouble getting information today, I would have expected them to make comments to that effect, like "the group is still unable to obtain necessary information".
That’s for sure. Today’s information is superb: we have detailed information about the water processing facility, the radiation measurements, the levels of water in the pits and the access to the reactor’s buildings.
I am sure a Western country would have concealed it on grounds of National security.
I was referring to the results of the IAEA delegation to Japan:
“TOKYO, May 25 (Xinhua) — A delegation of nuclear experts from the International Atomic Energy Agency visiting Japan on a fact- finding mission to establish the cause of the nuclear disaster at the Fukushima No. 1 nuclear power plant, the worst since the 1986 Chernobyl crisis, said Wednesday that their investigations are on “behalf of the world” and will be fair and objective.”
Upon return they had this closed door session wherein they said they were unable to get the information needed.